bonsoir

- 2 x² = 0 ⇔ x = 0

( x - 2)² = 9

( x - 2)² - 9 = 0

( x - 2 - 3) ( x - 2 + 3) = 0

( x - 5) ( x + 1) = 0 donc x = 5 ou - 1